1. Field of the Invention
The present invention relates to an oil receiver for introducing lubricating oil into a shaft body from the outside.
2. Description of Background Art
When introducing lubricating oil into a shaft body from the outside, an oil receiver is provided for supplying lubricating oil. The oil receiver includes a connecting oil passage formed on the outer periphery of the shaft body which communicates with a communication hole extending from the inside to the outside of the shaft body.
For example, in the case of an aircraft, hydraulic pressure for varying the pitch of the propeller is supplied through an oil passage located inside the revolving shaft of the propeller. An oil receiver is formed around the outer periphery of the revolving shaft of the propeller for introducing lubricating oil from an external hydraulic pressure varying unit into the oil passage inside the revolving shaft of the propeller.
The construction of an oil receiver according to the background art is illustrated in FIGS. 6 and 7 of the present invention.
Referring to FIGS. 6 and 7, the crankshaft 03 of the internal combustion engine directly rotates a propeller. The crankshaft 03 is rotatably supported by the cylinder block 01 of the internal combustion engine via a bearing 02. The crankshaft 03 is cylindrical in shape and is fitted therein with an inner cylinder 04. The clearance between the crankshaft 03 and the inner cylinder 04 is used as the oil passage 05.
The communication holes 06 open at positions upstream of the oil passage 05 and are formed, for example, at every 180° circumferentially of the crankshaft 03. An oil receiver 07 is mounted so as to cover the plurality of communication holes 06 on the outer periphery of the crankshaft 03.
The oil receiver 07 forms an annular oil passage 08 along the outer peripheral surface of the crankshaft 03. The aforementioned two communication holes 06 communicate with the annular oil passage 08.
A lead-in oil passage 09 extends integrally from a part of the annular oil passage 08 radially outward. An extremity of the lead-in oil passage 09 is fitted and connected in a joint pipe 01a, which projects from the inner surface of the cylinder block 01 in a liquid-tight manner.
Lubricating oil supplied from the hydraulic pressure varying unit is introduced into the annular oil passage 08 from the joint pipe 01a through the lead-in oil passage 09. The lubricating oil then flows into the oil passage 05 in the crankshaft 03 through the communication holes 06, and reaches the propeller pitch varying unit at the propeller boss at the extremity of the crankshaft. Accordingly, the pitch of the propeller can be varied.
The oil receiver 07 is fixed in contrast to the rotating crankshaft 03 and is in sliding contact with the crankshaft 03. Furthermore, the oil receiver 07 is formed with a stopper 07a, which is to be locked by a part of the cylinder block 01 for preventing the oil receiver 07 from rotating together with the crankshaft 03.
The oil receiver 07 is divided into two halves and includes a left half and the right half. The respective oil receiver halves 07L, 07R clamp the crankshaft 03 from the left and the right. The fastening bosses on the top and bottom are fastened with bolts 010, 011. The lead-in oil passage 09 is formed integrally on the right oil receiver half 07R (left side in FIG. 7).
The hydraulic pressure introduced into the lead-in oil passage 09 of the oil receiver 07 is introduced from the joint pipe 01a. Accordingly, the hydraulic pressure in the joint pipe 01a is applied on the end surface of the opening of the lead-in oil passage 09. This pressure P constantly presses the right oil receiver half 07R leftward (rightward in FIG. 7), which increases friction with respect to the crankshaft 03, which is in sliding contact therewith. As a consequence, the amount of consumption of fuel may increase and the progression of abrasion may be accelerated.
The oil receiver 07 is prevented from being rotated together with the rotation of the crankshaft 03 by the lead-in oil passage 09 fitted into the joint pipe 01a of the cylinder block 01. However, this is an insufficient way to prevent rotation of the oil receiver 07. Accordingly, the stopper 07a is also separately locked by a part of the cylinder block.
The lead-in oil passage 09 is formed integrally on the right oil receiver half 07R, and the stopper 07a is formed integrally on the left oil receiver half 07L. Therefore, the left and right oil receiver halves 07L, 07R are not symmetrical, and hence are not identical in shape. As a consequence, two types of oil receiver halves must be provided.